Eric Lee / smarc-fsl-linux-kernel

07 Jan, 2016

1 commit

14 Mar, 2015

2 commits

  • 297d716f6   power_supply: Change ownership from driver to core ... Browse Code »

    Change the ownership of power_supply structure from each driver
    implementing the class to the power supply core.

    The patch changes power_supply_register() function thus all drivers
    implementing power supply class are adjusted.

    Each driver provides the implementation of power supply. However it
    should not be the owner of power supply class instance because it is
    exposed by core to other subsystems with power_supply_get_by_name().
    These other subsystems have no knowledge when the driver will unregister
    the power supply. This leads to several issues when driver is unbound -
    mostly because user of power supply accesses freed memory.

    Instead let the core own the instance of struct 'power_supply'. Other
    users of this power supply will still access valid memory because it
    will be freed when device reference count reaches 0. Currently this
    means "it will leak" but power_supply_put() call in next patches will
    solve it.

    This solves invalid memory references in following race condition
    scenario:

    Thread 1: charger manager
    Thread 2: power supply driver, used by charger manager

    THREAD 1 (charger manager) THREAD 2 (power supply driver)
    ========================== ==============================
    psy = power_supply_get_by_name()
    Driver unbind, .remove
    power_supply_unregister()
    Device fully removed
    psy->get_property()

    The 'get_property' call is executed in invalid context because the driver was
    unbound and struct 'power_supply' memory was freed.

    This could be observed easily with charger manager driver (here compiled
    with max17040 fuel gauge):

    $ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
    $ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
    [ 55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
    [ 55.732584] pgd = d98d4000
    [ 55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
    [ 55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
    [ 55.746210] Modules linked in:
    [ 55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G W 3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
    [ 55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
    [ 55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
    [ 55.771647] PC is at 0x0
    [ 55.774182] LR is at charger_get_property+0x2f4/0x36c
    [ 55.779201] pc : [] lr : [] psr: 60000013
    [ 55.779201] sp : daf55e90 ip : 00000003 fp : 00000000
    [ 55.790657] r10: 00000000 r9 : c06e2878 r8 : d9b26c68
    [ 55.795865] r7 : dad81610 r6 : daec7410 r5 : daf55ebc r4 : 00000000
    [ 55.802367] r3 : 00000000 r2 : daf55ebc r1 : 0000002a r0 : d9b26c68
    [ 55.808879] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
    [ 55.815994] Control: 10c5387d Table: 598d406a DAC: 00000015
    [ 55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
    [ 55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
    [ 55.831795] 5e80: 60000013 c01459c4 0000002a c06f8ef8
    [ 55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
    [ 55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
    [ 55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
    [ 55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
    [ 55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
    [ 55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
    [ 55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
    [ 55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
    [ 55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
    [ 55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
    [ 55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
    [ 55.929744] [] (charger_get_property) from [] (power_supply_show_property+0x48/0x20c)
    [ 55.939286] [] (power_supply_show_property) from [] (dev_attr_show+0x1c/0x48)
    [ 55.948130] [] (dev_attr_show) from [] (sysfs_kf_seq_show+0x84/0x104)
    [ 55.956298] [] (sysfs_kf_seq_show) from [] (kernfs_seq_show+0x24/0x28)
    [ 55.964536] [] (kernfs_seq_show) from [] (seq_read+0x1b0/0x484)
    [ 55.972172] [] (seq_read) from [] (__vfs_read+0x18/0x4c)
    [ 55.979188] [] (__vfs_read) from [] (vfs_read+0x7c/0x100)
    [ 55.986304] [] (vfs_read) from [] (SyS_read+0x40/0x8c)
    [ 55.993164] [] (SyS_read) from [] (ret_fast_syscall+0x0/0x48)
    [ 56.000626] Code: bad PC value
    [ 56.011652] ---[ end trace 7b64343fbdae8ef1 ]---

    Signed-off-by: Krzysztof Kozlowski
    Reviewed-by: Bartlomiej Zolnierkiewicz

    [for the nvec part]
    Reviewed-by: Marc Dietrich

    [for compal-laptop.c]
    Acked-by: Darren Hart

    [for the mfd part]
    Acked-by: Lee Jones

    [for the hid part]
    Acked-by: Jiri Kosina

    [for the acpi part]
    Acked-by: Rafael J. Wysocki

    Signed-off-by: Sebastian Reichel

    Krzysztof Kozlowski
     
  • 2dc9215d7   power_supply: Move run-time configuration to separate structure ... Browse Code »

    Add new structure 'power_supply_config' for holding run-time
    initialization data like of_node, supplies and private driver data.

    The power_supply_register() function is changed so all power supply
    drivers need updating.

    When registering the power supply this new 'power_supply_config' should be
    used instead of directly initializing 'struct power_supply'. This allows
    changing the ownership of power_supply structure from driver to the
    power supply core in next patches.

    When a driver does not use of_node or supplies then it should use NULL
    as config. If driver uses of_node or supplies then it should allocate
    config on stack and initialize it with proper values.

    Signed-off-by: Krzysztof Kozlowski
    Reviewed-by: Bartlomiej Zolnierkiewicz
    Acked-by: Pavel Machek

    [for the nvec part]
    Reviewed-by: Marc Dietrich

    [for drivers/platform/x86/compal-laptop.c]
    Reviewed-by: Darren Hart

    [for drivers/hid/*]
    Reviewed-by: Jiri Kosina

    Signed-off-by: Sebastian Reichel

    Krzysztof Kozlowski
     

09 Mar, 2015

1 commit

20 Oct, 2014

1 commit

07 Jun, 2013

1 commit

22 Feb, 2013

1 commit

  • b5c78e04d   Merge tag 'staging-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging ... Browse Code »

    Pull staging tree update from Greg Kroah-Hartman:
    "Here's the big staging tree merge for 3.9-rc1

    Lots of cleanups and updates for drivers all through the staging tree.
    We are pretty much "code neutral" here, adding just about as many
    lines as we removed.

    All of these have been in linux-next for a while."

    * tag 'staging-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (804 commits)
    staging: comedi: vmk80xx: wait for URBs to complete
    staging: comedi: drivers: addi-data: hwdrv_apci3200.c: Add a missing semicolon
    staging: et131x: Update TODO list
    staging: et131x: Remove assignment of skb->dev
    staging: wlan-ng: hfa384x.h: fix for error reported by smatch
    staging/zache checkpatch ERROR: spaces prohibited around that
    staging/ozwpan: Mark read only parameters and structs as const
    staging/ozwpan: Remove empty and unused function oz_cdev_heartbeat
    staging/ozwpan: Mark local functions as static (fix sparse warnings)
    staging/ozwpan: Add missing header includes
    staging/usbip: Mark local functions as static (fix sparse warnings)
    staging/xgifb: Remove duplicated code in loops.
    staging/xgifb: Consolidate return paths
    staging/xgifb: Remove code without effect
    staging/xgifb: Remove unnecessary casts
    staging/xgifb: Consolidate if/else if with identical code branches
    staging: vt6656: replaced custom TRUE definition with true
    staging: vt6656: replaced custom FALSE definition with false
    staging: vt6656: replace custom BOOL definition with bool
    staging/rtl8187se: Mark functions as static to silence sparse
    ...

    Linus Torvalds
     

17 Feb, 2013

1 commit

  • 64d26f225   generic-adc-battery: Fix forever loop in gab_remove() ... Browse Code »

    There is a forever loop calling iio_channel_release() because the
    "chan < " part of the "chan < ARRAY_SIZE()" is missing. This is in both
    the error handling on probe and also in the remove function.

    The other thing is that it's possible for some of the elements of the
    adc_bat->channel[chan] array to be an ERR_PTR(). I've changed them to be
    NULL instead. We're still not allowed to pass NULLs to
    iio_channel_release() so I've added a check.

    Finally, I removed an unused "chan = ARRAY_SIZE(gab_chan_name);" statement
    as a small cleanup.

    Signed-off-by: Dan Carpenter
    Signed-off-by: Anton Vorontsov

    Dan Carpenter
     

07 Feb, 2013

1 commit

12 Dec, 2012

1 commit

29 Nov, 2012

3 commits

17 Nov, 2012

1 commit

16 Nov, 2012

1 commit

22 Sep, 2012

1 commit

  • e60fea794   power: battery: Generic battery driver using IIO ... Browse Code »

    Driver to allow use of the ADC drivers supported by the IIO
    subsystem for battery status monitoring. Connecting this
    driver to the relevant IIO device requires registration of
    the appropriate iio_map structure array by the IIO device
    driver (usually from platform data). If specified the driver
    will also make use of a gpio to provide interrupt driven
    notification that the battery is fully charged.

    In last version:
    Addressed concerns raised by lars:
    a. made the adc_bat per device.
    b. get the IIO channel using hardcoded channel names.
    c. Minor issues related to gpio_is_valid and some code
    refactoring.

    In V1:
    Addressed concerns raised by Anton:
    a. changed the struct name to gab(generic adc battery).
    b. Added some functions to neaten the code.
    c. Some minor coding guidelines changes.
    d. Used the latest function introduce by lars:
    iio_read_channel_processed to streamline the code.

    In V2:
    Addressed concerns by lars:
    a. No need of allocating memory for channels.Make it array.
    b. Code restructring, coding style and following kernel guidelines changes
    suggested by him.

    In V3:
    Addressed conerns by Anton:
    a. Added the copyright.
    b. Coding guidelines changes suggested by him.
    c. Added Makefile and Kconfig

    Signed-off-by: anish kumar
    Acked-by: Anton Vorontsov
    Signed-off-by: Jonathan Cameron

    anish kumar